The present invention relates to a convertible forage-handling machine in general, and more particularly to a machine of this type which is capable of being converted for performing a tedding operation, on the one hand, and for forming swaths of forage, on the other hand.
There is already known a variety of machines of the type here under consideration, each of which includes at least one raking wheel which rotates about its axis and which includes a plurality of tool-carrying arms that extend outwardly from the axis of rotation and orbit the latter in the course of rotation of the raking wheel. These arms carry at their ends which are remote from the axis of the raking wheel a plurality of forage-engaging tools or tines capable of gathering or transporting forage, such as hay, as the raking wheel rotates. Usually, that end of the respective arm which is close to the axis of rotation of the raking wheel is equipped with a crank which carries a roller follower that traces a cam track of a cam member which is stationarily mounted on the machine. The configuration of the cam track, which may be shaped as a guiding groove, is so selected that the respective tool-carrying arm is swivelled back and fourth about its longitudinal axis at certain points of the trajectory of its orbiting movement about the axis of the raking wheel to lift the forage-engaging tools off the ground and to subsequently return such tools to their original positions to engage additional quantities of forage, when the machine operates in its windrowing position. This swivelling motion of the arms, which results in a periodical lifting of the forage-engaging tools off the ground, results in the deposition of the forage in respective swaths.
When a machine of this type, which usually has more than one of the raking wheels, is to be converted from the windrowing position to the tedding position, the swivelling motion of the arms, which results in periodical lifting of the forage-engagement elements at certain points of their orbiting trajectories, must be discontinued so that the forage-engaging tools remain in their positions of substantial perpendicularity to the ground at the front of the machine as seen in the advancement direction of the latter. It is also advantageous, for operating in the tedding position, to increase the range of operation of the forage-engaging teeth in the radial direction of the raking wheel, as compared to the radius along which the forage-engaging teeth travel during the operation in the windrowing position.
To achieve these purposes, there has been proposed a machine of the type here under consideration in which each of the tool-carrying arms consists of two parts. In this conventional machine, these two parts of each of the arms are connected with one another when the machine is to perform in the windrowing position, while they are separated from each other for operation in the tedding position. This function has the disadvantage that a ball of hay or other forage will form between the two parts of each of the arms. Furthermore, each of the arms is to be equipped with a separate device for connecting the two parts of each of the arms for joint rotation when the machine is operating in the windrowing position. Since each of the arms is equipped with its own connecting device so that each of the connecting devices has to be adjusted for changing from the tedding position to the windrowing position and vice versa, it will be appreciated that a substantial amount of time is spent on this change from one mode of operation to the other. The amount of time spent in this converting operation is further extended by the fact that, at least during the change from the tedding position to the windrowing position, it is necessary to clear the ends of the two parts of each of the arms which face one another of any hay or other forage which may have beconme accumulated or deposited thereon, in order to be able to cause the connecting means to interconnect the two parts of each of the arms.
Furthermore, there are known other machines of this type wherein each of the arms again consists of two parts which, however, are always in contact with one another, whether the machine is to be operated in the tedding position or in the windrowing position. A particular advantage of this construction of the forage-handling machine of this type is that it is not necessary to provide the connecting device of the above-discussed type. However, this machine is also disadvantageous in several respects. So, for instance, it is impossible to change the radial distance at which the forage-engaging elements or tools orbit the axis of the raking wheel when changing from one of the modes of operation to the other. This, of course, is disadvantageous, particularly in view of the fact that, in order to obtain efficient tedding, it is necessary to reduce the distance between two adjoining raking wheels so as to preferably obtain interpenetration or interleaving of the arms or forage-engaging tools or elements as they orbit about the axes of the corresponding raking wheels. This need for providing for the adjustment of the distance between the individual raking wheels renders the construction of this machine very complex and, consequently, prone to malfunction.
Another conventional machine of this type where the arms of the raking wheel each also consist of two parts, is so constructed as to render it possible to increase the diameter of orbiting motion of the forage-engaging teeth about the axes of the respective raking wheels when converting from the windrowing position to the tedding position. This machine is equipped with a latching device which latches the arms of each raking wheel against rotation when such arms assume their extended positions corresponding to the tedding position. This machine employs a multitude of universal joints for interconnecting the parts of the individual arms; hence, this machine is rather sensitive to soiling and resulting damage. In addition thereto, it is necessary in this machine to move the outer parts of each arm between their extended and retracted positions from one plane in another. This, of course, is very disadvantageous.